The present invention relates to a network management system for managing a managed device via, for example, a network, and more particularly to a management object process unit incorporated in the managed device as an agent, and a machine readable recording medium having a management object process program recorded thereon.
In the network management system, generally, a host device is connected to a managed device, such as, for example, a printer, a facsimile, or a computer via a network, such as a LAN (Local Area Network). Management is performed on the basis of mainly SNMP (Simple Network Management Protocol) commands transmitted and received between a manager incorporated in the host device and the agent incorporated in the managed device. The agent receives a request transmitted in the form of the SNMP command from the manager and transmits a response for the request in the form of the SNMP command to the manager. In the transmission and reception of the SNMP commands, a communication protocol such as a TCP/IP is utilized.
The SNMP command from the manager requests a management object such as structure information, status information, or the like. The agent collects the management object for this request from the managed device to transmit the response containing this management object. However, when the agent or the managed device is busy, there is a case in which a long elapse of time is required before transmission of the response for the request, or no response is transmitted due to the property of the protocol. Thus, the manager transmits the same request again if the response is not received within a predetermined period of time. When this request is frequently repeated, the network traffic increases.
Jpn. Pat. Appln. KOKAI Publication No. 9-259062 discloses an agent capable of solving the problem described above. This agent is constituted so as to collect a plurality of management objects from the managed device in advance, store them in a memory device, and retrieve the management object requested by an SNMP manager from this memory device so that effective collection time for the management object is reduced to attain a quick response.
With the agent of the publication, all management objects are unconditionally collected in advance and stored in the memory device. This structure permits that the total collection time becomes longer according to an increase in the number of management objects. If collection of all the management objects cannot be completed while the managed device is not busy, some of the management objects are not stored in the memory device before the manager requests collection thereof. This causes a problem that the management objects are not effectively collected for the load of the agent. Further, the process for collecting the management objects in advance is independently executed of the process for transmitting a response for the request issued from the SNMP manager. This causes another problem that a complicated structure is required for the agent.